Method of trimming gates of die castings



Feb. 3, 1948. H. MORIN 2,435,505

METHOD OF TRIMMING GATES OF DIE CASTINGS Original Filed Jan. 15, 1943 IN VEN TOR Lou/s H MOP/N A TTORNE Y Patented Feb. 3, 1948 METHOD or 'r: h on G earns or nm css'rmcs Louis H. Morin, Bronx, N. Y., assiznor of onehalf to Davis Marinsky, Bronx, N. Y.

Original application January 15, 1943, Serial No. 472,492. Divided and this application January 13, 1944, Serial No. 518,196

6 Claims. 1

This invention relates to the formation or die castings including gate portions where the casting is formed on a core, the latter serving to eject the castings from the dies in the separation of said dies. More particularly, the invention re latcs to the method of trimming gates from die castings while the casting is supported on the core and prior to stripping the casting from the core, thereby producing a substantially finished casting removed from the machine in the stripping operation. The novel features of the invention will be best understood from the following description when taken together with the accompanying drawing, in which certain embodiments of the invention are disclosed, and in which the separate parts are designated by suitable reference characters in each of the views; and in which:

Fig. 1 is a diagrammatic exploded perspective view showing the dies in open position with the casting supported on a core, and illustrating the trimming and stripper tools.

Fig. 2 is a view similar to Fig. 1, showing parts in difierent positions. 5

Fig. 3 is a sectional detailed view along the parting line of relatively movable dies, illustrating another form of trimming and stripper elements; and

Fig. 4 is a view similar to Fig. 3, showing parts in a different position.

This application is a division of my prior application for a patent on Method of trimming gates of die castings, Serial Number 472,492, filed January 15, 1943, now Patent No. 2,375,486, issued May 8, 1945, and .deals more specifically with the method as disclosed in Figs. 3 and 4 of the drawing.

In the art of forming die castings. it has been more 01' less the conventional practise to form a casting and then after removal from the machine to trim the gate portion from the casting in a separate operation. In other instances, where castings have been formed on a, core, it has been customary to first strip or remove the casting from the core and then to trim the same in the removal or the gate from the casting.

It is the purpose of my present invention to employ a method which simplifies and economizes on the present practises in reducing the number of handlings of a casting for trimming and similar operations, and also to eifect more accurate trimming operations by removing the gate before stripping the casting from the core on which the casting is supported after the dies have been separated.

In the accompanying drawing, two adaptations of this invention are disclosed, but in both instances, a trimming or gate removing tool is first actuated to remove the gate from the castinfl after which another tool or stripper engages the casting in removing it from its core.

The method as disclosed in Figs. 1 and 2 of the drawing show the various parts of the apparatus diagrammatically and also in what might be termed exaggerated relationship, particularly in that the two die parts l0 and II are shown in wide spaced relationship in order to clearly illustrate the gate trimming tool or member l2 and the stripper I3.

011 abutting surfaces of the dies l0 and" are cavities or impressions H which collectively form what may be termed a button shank I5, comprising as noted in Fig. 2, a disc like body IS with a depending ring or eye portion ll. The disc 16 has an aperture l8 in the upper surface thereof, formed by the reduced end IQ of a core pin 20.

Also formed on the abutting surfaces of the dies I0 and H are admission passages 2| through which casting material from an injection nozzle 22 is pressure fed into the cavity or impression I4 in forming the resulting casting l5, upon the lower end of the core 20. The passage 2|, where it joins the cavity I4 is contracted, as seen at 23,

to form on the resulting gate 24 a weakened end 25 which facilitates removal of the gate 24 and dispenses with the use of a sharp trimming tool. It will here be understood, however, that in some instances sharp trimming tools may be employed to actually shear the gate adjacent or at the periphery ofgthe casting.

The trimming tool l2 in the construction shown, comprises a bar movable transversely with respect to movement of the core 20, and has at its inner end an aperture or pocket 26 to receive the gate 24 when the core 20 is lowered to the trimming position, as shown in full lines in Fig. 1, After the core has been moved into this position, the stripper tool 13 is moved in the direction of the core 20 so that the forked end of 21 thereof envelops the core, as seen in Fig. 1.

2,4as,ooo I The trimming tool I! is now moved in the direction or the arrow 20 as indicated by the dotted lines in Fig. 1, which results in removing or trimming the gate 24 from the casting l5. Immediately upon completion of this operation, the core 20 is then moved upwardly in the direction of the arrow 29 of Fig. 2, which results in stripping the casting to therefrom by the stripper l3. The stripper is then moved into retracted position, the dies in and II again moved into closed position upon the core 20, the nozzle brought into engagement with the dies, and the next successive casting is formed.

After the casting is formed, the dies in and H are separated as indicated in Fig, 1, leaving the casting I supported on the core as indicated in the dotted position of these parts in Fig. 1, the core 20 being used to eject the castings from the impressions i4. Thereafter, the above operation is again repeated to trim and eject the next successive casting.

Castings of this type and kind can be produced at high rates of speed, and will result in production of finished products, except where plating and other operations might be desirable.

It will be understood that the particular article or casting shown in the accompanying drawing is simply illustrative of one of many types and kinds of castings which can be produced in this manner. Where mass production is desired and excessive handling dispensed with for the purpose of minimizing, to the greatest degree, the cost of production, suitable means will be provided in the die casting machine for delivering the finished trimmed articles to containers. These containers may be in the form of shipping cases or cartons, automatically moved into receiving position by controlled counters, which will count the number of castings formed and delivered to each container. In other instances, the castings may be collected in bulk and simply weighed out for packaging and distribution.

In Figs. 3 and 4 of the drawing is shown a slight modification which consists primarily in substituting for the trimming tool l2 and stripper l3 a combined trimming tool 30 and stripper 3|, arranged upon the core 20 above the dies III, II instead of beneath the dies, as shown in Figs. 1 and 2.

With this construction and method of operation, the core 20 moves upwardly-when the dies Ill-ll are separated, instead of moving downwardly as in Figs. 1 and 2. The trimming and stripping tools 30, 3| are held stationary, and as the tool 30 projects below the lower surface of the stripper 3|, this tool will first engage the gate 24 of the casting Ii to remove or trim it from the casting. after which the continued upward movement of the core will result in stripping the casting I5 from the core, as is illustrated in Fig. 4 of the drawing.

In some types and kinds of casting, the method of procedure as illustrated in Figs. 3 and 4, would 4 downwardly in performing their combined trimming and stripping operations.

Having fully described my invention, what I claim as new and desire to secure by Letters Patent is:

1. The method of trimming gate portions from die castings, which comprises first forming a die casting between relatively movable dies and on a be desirable over the method illustrated in Figs.

core arranged on the parting line of the dies, by injecting casting material through a gate passage on the parting line of the dies into the mold cavity of said die and around said core, then separating the dies, leaving the casting including a gate portion supported on said core, arranging a combined trimming and stripper tool on the core in spaced relation to the dies, then operating the core to move the casting in the direction of said tool to first trim the gate portion from the casting, and then in the continued movement of the core in the same direction to strip the casting i'rom the core.

2. The method of trimming die castings, which comprises first forming a casting including a gate portion on a core member between relatively movable dies, arranging trimming and stripping tools adjacent said member and in spaced relation to the dies, separating the dies, leaving the casting supported on the core member, then moving the core member and said casting out of the path of movement of said dies and toward said tools, first trimming the gate portion from the casting, while supported on the core member, in said movement of the core member, and then stripping the casting from thecore member in continued movement of the core member in the same direction in completing said movement.

3. The method of producing die castings, which comprises forming a die casting including a gate portion on a member and betweenrelatively movable dies, using said member to eject the casting from the dies in the separation thereof, arranging trimming and stripping tools-adjacent said member and in spaced relation to the dies,

moving said member with the casting thereon relatively to the dies to first remove the gate portion from the casting supported on said member, and then in the continued movement of said member in the same direction to strip the trimmed casting from said member.

4. The method of trimming castings and stripping the same from a member on which the casting is formed, which comprises arranging combined trimming and stripping tools in close proximity to said member, then moving said member in the direction of said tools to first trim the casting while supported on the member, and then in the same directional movement of said member to strip the trimmed casting therefrom.

5. The method of trimming casting and stripping the same from a member on which the casting is formed, which comprises arranging trimming and stripping tools in close proximity to said member, forming a casting on said member between relatively movable dies, separating the dies, leaving the casting on said member, and then moving the member and tools one relatively to the other to first trim the casting and then in a continued unidirectional movement in the same direction to strip the casting from said member.

6. The method of producing die castings, which comprises forming a die casting including a gate portion on a member and between relatively movable dies, using said member to eject the casting from the dies in the separation thereof, arrangensues REFERENCES CITED 1.

The following references are of record in the file of this patent:

Number UNITED STATES PATENTS Name Date Morin et al Dec. 11, 1934 Morin et al June 18, 1935 Morin et al Jan. '1, 1941 Morin et a1 "Nov. 11, 1941 

